首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   25507篇
  免费   1067篇
  国内免费   484篇
财政金融   1544篇
工业经济   1272篇
计划管理   7369篇
经济学   3326篇
综合类   5024篇
运输经济   198篇
旅游经济   220篇
贸易经济   3152篇
农业经济   1955篇
经济概况   2997篇
信息产业经济   1篇
  2024年   10篇
  2023年   144篇
  2022年   256篇
  2021年   411篇
  2020年   512篇
  2019年   247篇
  2018年   220篇
  2017年   311篇
  2016年   357篇
  2015年   688篇
  2014年   1859篇
  2013年   1522篇
  2012年   2313篇
  2011年   2880篇
  2010年   2266篇
  2009年   1860篇
  2008年   2157篇
  2007年   1995篇
  2006年   1972篇
  2005年   1495篇
  2004年   1133篇
  2003年   787篇
  2002年   514篇
  2001年   419篇
  2000年   298篇
  1999年   151篇
  1998年   66篇
  1997年   57篇
  1996年   35篇
  1995年   19篇
  1994年   26篇
  1993年   22篇
  1992年   18篇
  1991年   5篇
  1990年   9篇
  1989年   6篇
  1988年   1篇
  1987年   4篇
  1986年   1篇
  1985年   3篇
  1984年   4篇
  1983年   3篇
  1981年   2篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
1.
Despite the extensive amount of data generated and stored during the maintenance capacity planning process, Maintenance, Repair, and Overhaul (MRO) organizations have yet to explore their full potential in forecasting the required capacity to face future and unprecedented maintenance interventions. This paper explores the integration of time series forecasting capabilities in a tool for maintenance capacity planning of complex product systems (CoPS), intended to value data that is routinely generated and stored, but often disregarded by MROs. State space formulations with multiplicative errors for the simple exponential smoothing (SES), Holt’s linear method (HLM), additive Holt-Winters (AHW), and multiplicative Holt-Winters (MHW) are assessed using real data, comprised of 171 maintenance projects collected from a major Portuguese aircraft MRO. A state space formulation of the MHW, selected using the bias-corrected Akaike information criterion (AICc), is integrated in a Decision Support System (DSS) for capacity planning with probabilistic inference capabilities and used to forecast the workload probability distribution of a future and unprecedent maintenance intervention. The developed tool is validated by comparing forecasted values with workloads of a particular maintenance intervention and with a model simulating current forecasting practices employed by MROs.  相似文献   
2.
The prevalence of online health communities (OHCs) motivates health product companies to manipulate persuasion-based marketing strategies, including fear appeals and coping appeals, to promote health products. However, whether such a practice is effective remains unclear. Respondents may either impulsively purchase the recommended health products or simply distance themselves psychologically from the information. Building on protection motivation theory (PMT), this study uncovers the mechanisms behind these two coping responses to persuasive messages, namely, the impulsive purchasing and psychological distancing of OHC users. Correspondingly, we evaluated 366 valid questionnaires, and the results reveal that (1) when encountering fear appeals, perceived health threat can evoke cyberchondria, leading to psychological distancing; and (2) when encountering coping appeals, perceived response efficacy leads to product affection, fostering impulsive purchasing. This study provides new insights into the effects of persuasive messages for health product promotion in social commerce. Marketers should design appropriate persuasive messages to foster impulsive purchasing by generating individuals’ product affection and avoiding cyberchondria.  相似文献   
3.
While the tourism sector shifts towards digital transformation, Destination Management Organisations (DMOs) often struggle to adapt to their changing technological environment. This study explores the antecedents of digital collaboration and develops a framework for micro-DMOs to enhance effective destination management through digital technologies. An integrated sequential qualitative approach was adopted by conducting multi-phase interviews, in addition to designing and trialling a real-world trial digital platform. The research provides empirical evidence that digital collaboration is essential for micro-DMOs, necessitating them to transform their current “websites” into digital platforms which act as a hub for business stakeholders to actively be involved in. Antecedents of successful digital collaboration include mutuality, trust, control, and leadership which may be manifested differently from non-digital collaboration. Additionally, the study identifies three aspects for digital collaboration; marketing, networking and knowledge sharing that demands specific attention. Our results have theoretical, methodological, and practical implications for academia, industry and policymakers.  相似文献   
4.
Drawing on the information system success model and perceived value theory, we develop a research model to examine factors that may affect user satisfaction and loyalty of mobile payment platforms. Empirical data was collected from users using Alipay and WeChat Pay in China, and a total of 410 valid responses were gathered for data analysis. The results show that the multi-dimensional formative perceived value including benefits and sacrifice is important determinant of mobile payment user satisfaction and loyalty. The three benefit dimensions of functional value, experiential value and social value are more important value components than the two sacrifice dimensions of risk and cost, and experiential value is the dominant component of mobile payment users' value perception. As for the antecedents of perceived value, system quality and service quality mainly affect perceived benefits, while information quality has a greater impact on risk. The research results provide the contribution of specific value dimensions to users' perceived value and the impact of quality characteristics on specific perceived value for mobile payment platform providers, thus helping them to adopt effective strategies to strengthen market competitiveness and retain existing users.  相似文献   
5.
蒋勇  魏蓉 《科技和产业》2023,23(15):86-91
装配式建筑供应链的运作存在很多不确定性。为提高供应链管理效率,促进建筑业的发展,运用供应链运作参考(SCOR)模型对装配式建筑供应链脆弱因子进行识别,将装配式供应链系统划分为6个子系统;通过系统动力学(SD)模型对供应链脆弱性进行仿真。结果表明,装配制造流程是脆弱性最大的子系统,整个供应链的脆弱性随着建筑项目的推进而增大。  相似文献   
6.
[目的]发展现代农业是促进我国经济社会快速发展的必然要求,结合当下现代化农业的发展情况,对黑龙江省农业综合开发进行评价,探讨多种农业发展的模式,为加快黑龙江省城镇化进程提供助力,为黑龙江省发展现代农业提供理论依据。[方法]通过实地调查法和文献查阅法对相关的研究内容进行汇总和分析。采用层次分析法(AHP)从基础资源设施、科技应用、生态建设、经济效益、政府管理、农村发展6个方面23个指标对黑龙江省农业综合开发进行评价,结合现代农业发展的趋势和黑龙江省农业业态配置情况,为黑龙江省未来农业发展模式提出建议。[结果]黑龙江省农业综合开发的评价指标体系中,生态建设和经济效益方面的权重值比较大,均为0.281 6;而农村发展、基础资源设施和政府管理水平有待提高。综合来看,黑龙江省农业综合开发整体较好,但是在其他方面存在发展不均衡的现象。[结论]黑龙江省农业综合开发进程良好,在农业发展中,基础资源设施、政府管理水平和农村发展水平都有待提高。今后,政府应该加强管理,重视生态文明建设,优化产业结构,发展"农业+生态"、"农业+旅游"、"农业+产业"等多种农业综合发展模式,促进黑龙江省农业更快速地发展,进而提升黑龙江省整体的城镇化水平。  相似文献   
7.
分析了当前国内外典型中小型特种飞机的特点和应用方向,阐述了中小型特种飞机系统的技术发展趋势。通过分析典型的特种通用飞机的性能和平台构型特点,详细描述了基于典型中小型特种飞机平台的机载侦察监视应用系统的组成、原理、主要性能及技术难点,并结合实际工程应用,介绍了系统的应用成果。应用分析表明,基于中小型特种飞机平台的机载平台的应用系统有较大的应用范围和市场前景。  相似文献   
8.
根据供给侧结构性改革的背景和基本内涵,对水资源供给侧结构性改革的内涵进行研究,提出了狭义和广义的水资源供给侧结构性改革的内容。在分析水资源需求新形势的基础上,提出了水资源供给侧结构性改革的要求。根据水循环理论提出了水资源管理是推动水资源供给侧结构性改革的重要抓手,并在最严格水资源管理制度的基础上,提出了符合水资源供给侧结构性改革要求的水资源管理制度。  相似文献   
9.
Models of cities based on conventional spatial market theory are unable to replicate a realistic size distribution. The stochastic process approach to size distribution, which assumes proportionate growth, does not provide an economic foundation for spatial trades. There is an apparent irreconcilability. We propose that since there is a continuum of equilibria in models of spatial markets with endogenous location, proportionate growth can work as equilibrium selection. We present computations for an urban configuration that has not been presented in the literature before. A small city locates inside a larger city's agricultural supply zone. This generates a larger variation in city size that may include a realistic size distribution.  相似文献   
10.
研究目的:阐明"三权"分置的制度逻辑,为制度供给的增量调整提供一种思路。研究方法:文献分析法、政策文本分析法。研究结果:当下农民、新型农业经营者出现新的制度诉求,既有土地承包经权营制度不足以满足该需求。承包地制度供给创新要做实承包权,辨明"三权"分置下经营权所处的位置。土地经营权的权利塑造过程应坚持物债二分法,实现物权法、合同法双重法制途径的并重。研究结论:承包地"三权"分置本质上是理论创新问题,辨清"三权"分置的制度逻辑,仍需以实践需求为出发点,新的制度供给是一个增量调整与立法跟进问题。对经营权性质的探讨有必要融入物债二分逻辑,对于短期限的土地经营权,应按照契约自由原则,实行意思主义,权利类型、权利内容经双方自由创设,对长期存续的土地经营权可实现物权化,实行物权法定主义,按照法定规格与程序流转。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号